Learning Forum

[user deleted]

Hello Everyone,

I'm currently learning the SPH method.
I'm using an implicit solver.
I'm trying to solve the problem of contact of 5 bodies, one of which is SF
Contacts type: nodes-surface

Unfortunately, the contacts do not work; the bodies penetrate each other.

I would be grateful for advice/hints.

 

Thanks in advance

Best Valery

[Jim Day]

Are you running implicit static or implicit dynamic?   What value have you assigned FORM in *CONTROL_SPH?   Which *MAT have you assigned the particles and does that material represent a solid material or a fluid?   Show me your *CONTROL_SPH data and your *CONTACT data.

[user deleted]

I develop laboratory work for students in the field of viscous media.
so I use implicit dynamic.

FORM in *CONTROL_SPH = 13

Now to debug the model, I use elastic linear material *MAT_ELASTIC

The model can be obtained from this link
https://filetransfer.io/data-package/tuA2nlvi#link

[user deleted]

[Jim Day]

Since you're using elastic material in this test, try FORM=0 in *CONTROL_SPH.   Set ITHK=1 in *CONTROL_SPH as well so that the radius of the particles are considered in the contact treatment.   Include *DATABASE_RCFORC will write histories of contact forces to rcforc; plot these forces to see if contact forces are being produced.   Set SOFT=1 in the *CONTACT input.

[user deleted]

thanks for the advice and kindness
but unfortunately there is no solution

*** Error 60038 (IMP+38)
     *********************************************************
     *                                                       *
     *              -  FATAL ERROR  -                        *
     *                                                       *
     *  Type 3 data conflict encountered in while            *
     *    assembling elemental matrices.                     *
     *  Invalid internal node number                         *
     *    internal node number =    2059                     *
     *    number of nodes      =    1226                     *
     *  Please report this message to LST.                   *
     *                                                       *
     *********************************************************

[Jim Day]

This may be an incompatibility between SPH and implicit.   In my own implicit test case, the SPH nodes never move.  As an experiment, try using the explicit solver and report what happens.

 

[user deleted]

SPH and explicit solver work successfully.